1. Field of the invention
The present invention relates to a trailer hitch designed for easily hitching a heavy trailer provided with a draw pole to a heavy motor vehicle, for example a truck.
In the present disclosure and in the appended claims, the term "trailer" is intended to designate any trailer, vehicle, machinery, or other equipment, wheeled or not, that can be drawn or hauled by a motor vehicle.
2. Brief Description of the Prior Art
U.S. Pat. No. 3.565.459 (REID) issued on Feb. 23, 1971, describes an automatic hitch including an inclined guide member to receive a vertical hitch pole secured to the free end of the draw pole of for example a trailer. As the tractor moves rearwardly, the hitch pole slides on the guide member to lift the hitch pole and guide it toward a jaw unit secured to the tractor and in which the hitch pole engages a pivotally mounted latch plate.
U.S. Pat. No. 4.225.149 (KOOPMAN) issued on Sept. 30, 1980, proposes a remotely operable trailer hitch including two pairs of forwardly converging guide plates forming a funnel, square in cross section and directing the coupling ring at the free end of a trailer draw pole toward an articulated J-shaped latch member, whereby the coupling ring engages the latch member upon rearward movement of the motor vehicle.
The above discussed prior art hitches are specifically designed for enabling mutual engagement of particular coupling members, namely a vertical hitch pole with a jaw unit and a coupling ring with a J-shaped latch member. They are not versatile enough to successively lift and lower the draw pole of a trailer for example to position a coupling ring on an upwardly oriented pintle hook.